Endoscopic full-thickness resection of T1 colorectal cancers: a retrospective analysis from a multicenter Dutch eFTR registry

Risk factors for lymph node metastasis in T2 colorectal cancer: a systematic review and meta-analysis

BACKGROUND

Lymph node metastasis (LNM) occurs in 20-25% of patients with T2 colorectal cancer (CRC). Identification of risk factors for LNM in T2 CRC may help identify patients who are at low risk and thereby potential candidates for endoscopic full-thickness resection. We examined risk factors for LNM in T2 CRC with the goal of establishing further criteria of the indications for endoscopic resection.

METHODS

MEDLINE, CENTRAL, and EMBASE were systematically searched from inception to November 2023. Studies that investigated the association between the presence of LNM and the clinical and pathological factors of T2 CRC were included. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Certainty of evidence (CoE) was assessed using the GRADE approach.

RESULTS

Fourteen studies (8349 patients) were included. Overall, the proportion of LNM was 22%. The meta-analysis revealed that the presence of lymphovascular invasion (OR, 5.5; 95% CI 3.7-8.3; high CoE), high-grade tumor budding (OR, 2.4; 95% CI 1.5-3.7; moderate CoE), poor differentiation (OR, 2.2; 95% CI 1.8-2.7; moderate CoE), and female sex (OR, 1.3; 95% CI 1.1-1.7; high CoE) were associated with LNM in T2 CRC. Lymphatic invasion (OR, 5.0; 95% CI 3.3-7.6) was a stronger predictor of LNM than vascular invasion (OR, 2.4; 95% CI 2.1-2.8).

CONCLUSIONS

Lymphovascular invasion, high-grade tumor budding, poor differentiation, and female sex were risk factors for LNM in T2 CRC. Endoscopic resection of T2 CRC in patients with very low risk for LNM may become an alternative to conventional surgical resection.

TRIAL REGISTRATION

PROSPERO, CRD42022316545.

Trends in incidence, treatment, and relative survival of colorectal cancer in the Netherlands between 2000 and 2021

BACKGROUND

The epidemiology of colorectal cancer (CRC) has changed rapidly over the years. The aim of this study was to assess the trends in incidence, treatment, and relative survival (RS) of patients diagnosed with CRC in the Netherlands between 2000 and 2021.

PATIENTS AND METHODS

2 75667 patients diagnosed with CRC between 2000 and 2021 were included from the Netherlands Cancer Registry. Analyses were stratified for disease extent (localised: T1-3N0M0; regional: T4N0M0/T1-4N1-2M0; distant: T1-4N0-2M1) and localisation (colon; rectum). Trends were assessed with joinpoint regression.

RESULTS

CRC incidence increased until the mid-2010s but decreased strongly thereafter to rates comparable with the early 2000s. Amongst other trend changes, local excision rates increased for patients with localised colon (2021: 13.6 %) and rectal cancer (2021: 34.9 %). Moreover, primary tumour resection became less common in patients with distant colon (2000-2021: 60.9-12.5 %) or rectal cancer (2000-2021: 47.8-6.9 %), while local treatment of metastases rates increased. Five-year RS improved continuously for localised and regional colon (97.7 % and 72.0 % in 2017, respectively) and rectal cancer (95.2 % and 76.3 % in 2017, respectively). The rate of anti-cancer treatments decreased in distant colon (2010-2021: 80.3 % to 67.2 %; p < 0.001) and rectal cancer (2011-2021: 86.0 % to 77.0 %; p < 0.001). The improvement of five-year RS stagnated for distant colon (2010-2017: 11.2 % to 11.9 %; average percentage of change [APC]: 2.1, 95 % confidence interval [CI]: -7.6, 4.7) and rectal cancer (2009-2017: 12.7 % to 15.6 %; APC: 1.4, 95 % CI: -19.1, 5.5).

CONCLUSIONS

Major changes in the incidence and treatment of CRC between 2000 and 2021 were identified and quantified. Five-year RS increased continuously for patients with localised and regional CRC, but stagnated for patients with distant CRC, likely caused by decreased rates of anti-cancer treatment in this group.

Technical failure during colorectal endoscopic full-thickness resection: the "through thick and thin" study

BACKGROUND

 Endoscopic full-thickness resection (EFTR) is an effective and safe technique for nonlifting colorectal lesions. Technical issues or failures with the full-thickness resection device (FTRD) system are reported, but there are no detailed data. The aim of our study was to quantify and classify FTRD technical failures.

METHODS

 We performed a retrospective study involving 17 Italian centers with experience in advanced resection techniques and the required devices. Each center shared and classified all prospectively collected consecutive failures during colorectal EFTR using the FTRD from 2018 to 2022. The primary outcome was the technical failure rate and their classification; secondary outcomes included subsequent management, clinical success, and complications.

RESULTS

 Included lesions were mainly recurrent (52 %), with a mean (SD) dimension of 18.4 (7.5) mm. Among 750 EFTRs, failures occurred in 77 patients (35 women; mean [SD] age 69.4 [8.9] years). A classification was proposed: type I, snare noncutting (53 %); type II, clip misdeployment (31 %); and type III, cap misplacement (16 %). Among endoscopic treatments completed, rescue endoscopic mucosal resection was performed in 57 patients (74 %), allowing en bloc and R0 resection in 71 % and 64 %, respectively. The overall adverse event rate was 27.3 %. Pooled estimates for the rates of failure, complications, and rescue endoscopic therapy were similar for low and high volume centers (P = 0.08, P = 0.70, and P = 0.71, respectively).

CONCLUSIONS

 Colorectal EFTR with the FTRD is a challenging technique with a non-negligible rate of technical failure and complications. Experience in rescue resection techniques and multidisciplinary management are mandatory in this setting.

T1 colorectal cancer management in the era of minimally invasive endoscopic resection

T1 colorectal cancer (CRC), defined by tumor invasion confined to the submucosa, has historically been managed by surgery. Improved understanding of recurrence and lymph node metastases risk, coupled with advances in endoscopic resection techniques, have led to an increasing capacity for organ-sparing local excision. Minimally invasive management of T1 CRC begins with optical evaluation of the lesion to diagnose invasive disease and quantify depth of invasion, which informs therapeutic decision making. Modality selection between various available endoscopic resection techniques depends upon lesion characteristics, technique risk-benefit profiles, and location-specific implications. Following endoscopic resection, established histopathology features determine the risk of recurrence and subsequent management including surveillance or adjuvant surgical excision. The management of non-operative candidates deviates from conventional recommendations with emerging treatment strategies in select populations.

Endoscopic full thickness resection: techniques, applications, outcomes

INTRODUCTION

Endoscopic full-thickness resection (EFTR) represents a pivotal advancement in the minimally invasive treatment of gastrointestinal lesions, offering a novel approach for the management of lesions previously deemed challenging or unreachable through conventional endoscopic techniques.

AREAS COVERED

This review discusses the development, methodologies, applications, and clinical outcomes associated with EFTR, including exposed and device-assisted EFTR (DA-EFTR), the integration of endoscopic mucosal resection (EMR) with EFTR in hybrid techniques, and the collaborative approach between laparoscopic and endoscopic surgery (LECS). It encapsulates a comprehensive analysis of the various EFTR techniques tailored to specific lesion characteristics and anatomical locations, underscoring the significance of technique selection based on the lesion's nature and situational context.

EXPERT OPINION/COMMENTARY

The review underscores EFTR's transformative role in expanding therapeutic horizons for gastrointestinal tumors, emphasizing the importance of technique selection tailored to the unique attributes of each lesion. It highlights EFTR's capacity to facilitate organ-preserving interventions, thereby significantly enhancing patient outcomes and reducing procedural complications. EFTR is a cornerstone in the evolution of gastrointestinal surgery, marking a significant leap forward in the pursuit of precision, safety, and efficacy in tumor management.

Additional staining for lymphovascular invasion is associated with increased estimation of lymph node metastasis in patients with T1 colorectal cancer: Systematic review and meta-analysis

OBJECTIVES

Lymphovascular invasion (LVI) is a critical risk factor for lymph node metastasis (LNM), which requires additional surgery after endoscopic resection of T1 colorectal cancer (CRC). However, the impact of additional staining on estimating LNM is unclear. This systematic review aimed to evaluate the impact of additional staining on determining LNM in T1 CRC.

METHODS

We searched five electronic databases. Outcomes were diagnostic odds ratio (DOR), assessed using hierarchical summary receiver operating characteristic curves, and interobserver agreement among pathologists for positive LVI, assessed using Kappa coefficients (κ). We performed a subgroup analysis of studies that simultaneously included a multivariable analysis for other risk factors (deep submucosal invasion, poor differentiation, and tumor budding).

RESULTS

Among the 64 studies (18,097 patients) identified, hematoxylin-eosin (HE) and additional staining for LVI had pooled sensitivities of 0.45 (95% confidence interval [CI] 0.32-0.58) and 0.68 (95% CI 0.44-0.86), specificities of 0.88 (95% CI 0.78-0.94) and 0.76 (95% CI 0.62-0.86), and DORs of 6.26 (95% CI 3.73-10.53) and 6.47 (95% CI 3.40-12.32) for determining LNM, respectively. In multivariable analysis, the DOR of additional staining for LNM (DOR 5.95; 95% CI 2.87-12.33) was higher than that of HE staining (DOR 1.89; 95% CI 1.13-3.16) (P = 0.01). Pooled κ values were 0.37 (95% CI 0.22-0.52) and 0.62 (95% CI 0.04-0.99) for HE and additional staining for LVI, respectively.

CONCLUSION

Additional staining for LVI may increase the DOR for LNM and interobserver agreement for positive LVI among pathologists.

Differentiation grade as a risk factor for lymph node metastasis in T1 colorectal cancer

Objectives

Japanese guidelines include high-grade (poorly differentiated) tumors as a risk factor for lymph node metastasis (LNM) in T1 colorectal cancer (CRC). However, whether the grading is based on the least or most predominant component when the lesion consists of two or more levels of differentiation varies among institutions. This study aimed to investigate which method is optimal for assessing the risk of LNM in T1 CRC.

Methods

We retrospectively evaluated 971 consecutive patients with T1 CRC who underwent initial or additional surgical resection from 2001 to 2021 at our institution. Tumor grading was divided into low-grade (well- to moderately differentiated) and high-grade based on the least or predominant differentiation analyses. We investigated the correlations between LNM and these two grading analyses.

Results

LNM was present in 9.8% of patients. High-grade tumors, as determined by least differentiation analysis, accounted for 17.0%, compared to 0.8% identified by predominant differentiation analysis. A significant association with LNM was noted for the least differentiation method (p < 0.05), while no such association was found for predominant differentiation (p = 0.18). In multivariate logistic regression, grading based on least differentiation was an independent predictor of LNM (p = 0.04, odds ratio 1.68, 95% confidence interval 1.00-2.83). Sensitivity and specificity for detecting LNM were 27.4% and 84.1% for least differentiation, and 2.1% and 99.3% for predominant differentiation, respectively.

Conclusions

Tumor grading via least differentiation analysis proved to be a more reliable measure for assessing LNM risk in T1 CRC compared to grading by predominant differentiation.

Challenges in Implementing Endoscopic Resection for T2 Colorectal Cancer

The current standard treatment for muscularis propria-invasive (T2) colorectal cancer is surgical colectomy with lymph node dissection. With the advent of new endoscopic resection techniques, such as endoscopic full-thickness resection or endoscopic intermuscular dissection, T2 colorectal cancer, with metastasis to 20%-25% of the dissected lymph nodes, may be the next candidate for endoscopic resection following submucosal-invasive (T1) colorectal cancer. We present a novel endoscopic treatment strategy for T2 colorectal cancer and suggest further study to establish evidence on oncologic and endoscopic technical safety for its clinical implementation.

Device-assisted endoscopic full-thickness resection in colorectum: Systematic review and meta-analysis

OBJECTIVES

Endoscopic full-thickness resection (EFTR) is emerging as an effective modality for mucosal and submucosal lesions in the colorectum. In this systematic review and meta-analysis, we aimed to analyze the success and safety of device-assisted EFTR in the colon and rectum.

METHODS

A literature search was performed in the Embase, PubMed, and Medline databases for studies evaluating device-assisted EFTR between inception to October 2022. The primary outcome of the study was clinical success (R0 resection) with EFTR. Secondary outcomes included technical success, procedure duration, and adverse events.

RESULTS

In all, 29 studies with 3467 patients (59% male patients, 3492 lesions) were included in the analysis. The lesions were located in right colon (47.5%), left colon (28.6%), and rectum (24.3%). EFTR was performed for subepithelial lesions in 7.2% patients. The pooled mean size of the lesions was 16.6 mm (95% confidence interval [CI] 14.9-18.2, I2 98%). Technical success was achieved in 87.1% (95% CI 85.1-88.9%, I2 39%) procedures. The pooled rate of en bloc resection was 88.1% (95% CI 86-90%, I2 47%) and R0 resection was 81.8% (95% CI 79-84.3%, I2 56%). In subepithelial lesions, the pooled rate of R0 resection was 94.3% (95% CI 89.7-96.9%, I2 0%). The pooled rate of adverse events was 11.9% (95% CI 10.2-13.9%, I2 43%) and major adverse events requiring surgery was 2.5% (95% CI 2.0-3.1%, I2 0%).

CONCLUSION

Device-assisted EFTR is a safe and effective treatment modality in cases with adenomatous and subepithelial colorectal lesions. Comparative studies are required with conventional resection techniques, including endoscopic mucosal resection and submucosal dissection.

Management of non-curative endoscopic resection of T1 colon cancer

Endoscopic resection techniques enable en-bloc resection of T1 colon cancers. A complete removal of T1 colon cancer can be considered curative when histologic examination of the specimens shows none of the high-risk factors for lymph nodes metastases. Criteria predicting lymph nodes metastases include deep submucosal invasion, poor differentiation, lymphovascular invasion, and high-grade tumor budding. In these cases, complete (R0), local endoscopic resection is considered sufficient as negligible risk of lymph nodes metastases does not outweigh morbidity and mortality associated with surgical resection. Challenges arise when endoscopic resection is incomplete (RX/R1) or high-risk histological features are present. The risk of lymph node metastasis in T1 CRC ranges from 1% to 36.4%, depending on histologic risk factors. Presence of any risk factor labels the patient "high risk," warranting oncologic surgery with mesocolic lymphadenectomy. However, even if 70%-80% of T1-CRC patients are classified as high-risk, more than 90% are without lymph node involvement after oncological surgery. Surgical overtreatment in T1 CRC is a challenge, requiring a balance between oncologic safety and minimizing morbidity/mortality. This narrative review explores the landscape of managing non-curative T1 colon cancer, focusing on the choice between advanced endoscopic resection techniques and surgical interventions. We discuss surveillance strategies and shared decision-making, emphasizing the importance of a multidisciplinary approach.

Curative criteria for endoscopic treatment of colorectal cancer

As endoscopic treatment enables en bloc resection of T1 colorectal cancers, the risk of recurrence, often assimilated to the risk of lymph node metastases, must be assessed in order to offer patients an additional treatment if this risk is deemed significant. The curative criteria currently used by most guidelines are depth of invasion <1 mm, well or moderately differentiated tumour, absence of lympho-vascular invasion, absence of significant budding and tumour-free resection margins. However, these factors must be assessed by qualified pathologists, as they are difficult to evaluate. Moreover, the combination of these factors leads to unnecessary surgery in over 80 % of patients whose tumours are classified as high risk. Refinement of current criteria and research into new tumour and immunological markers are needed to better predict the actual risk of our patients.

Management after non-curative endoscopic resection of T1 rectal cancer

Since the introduction of population-based screening, increasing numbers of T1 rectal cancers are detected and removed by local endoscopic resection. Patients can be cured with endoscopic resection alone, but there is a possibility of residual tumor cells remaining after the initial resection. These can be located intraluminally at the resection site or extraluminally in the form of (lymph node) metastases. To decrease the risk of residual cells progressing towards more advanced disease, additional treatment is usually needed. However, with the currently available risk stratification models, it remains challenging to determine who should and should not be further treated after non-curative endoscopic resection. In this review, the different management strategies for patients with non-curatively treated T1 rectal cancers are discussed, along with the available evidence for each strategy and relevant considerations for clinical decision making. Furthermore, we provide practical guidance on the management and surveillance following non-curative endoscopic resection of T1 rectal cancer.

Endoscopic full-thickness resection vs. endoscopic submucosal dissection of residual/recurrent colonic lesions on scars: a retrospective Italian and Japanese comparative study

BACKGROUND AND AIMS

Endoscopic treatment of recurrent/residual colonic lesions on scars is a challenging procedure. In this setting, endoscopic submucosal dissection (ESD) is considered the first choice, despite a significant rate of complications. Endoscopic full-thickness resection (eFTR) has been shown to be well-tolerated and effective for these lesions. The aim of this study is to conduct a comparison of outcomes for resection of such lesions between ESD and eFTR in an Italian and a Japanese referral center.

METHODS

From January 2018 to July 2020, we retrospectively enrolled patients with residual/recurrent colonic lesions, 20 treated by eFTR in Italy and 43 treated by ESD in Japan. The primary outcome was to compare the two techniques in terms of en-bloc and R0-resection rates, whereas complications, time of procedure, and outcomes at 3-month follow-up were evaluated as secondary outcomes.

RESULTS

R0 resection rate was not significantly different between the two groups [18/20 (90%) and 41/43 (95%); P= 0.66]. En-bloc resection was 100% in both groups. No significant difference was found in the procedure time (54 min vs. 61 min; P= 0.9). There was a higher perforation rate in the ESD group [11/43 (26%) vs. 0/20 (0%); P= 0.01]. At the 3-month follow-up, two lesions relapsed in the eFTR cohort and none in the ESD cohort (P= 0.1).

CONCLUSION

eFTR is a safer, as effective and equally time-consuming technique compared with ESD for the treatment of residual/recurrent colonic lesions on scars and could become an alternative therapeutic option for such lesions.

The 2022 top 10 list of endoscopy topics in medical publishing: an annual review by the American Society for Gastrointestinal Endoscopy Editorial Board

Using a systematic literature search of original articles published during 2022 in Gastrointestinal Endoscopy and other high-impact medical and gastroenterology journals, the 10-member Editorial Board of the American Society for Gastrointestinal Endoscopy composed a list of the 10 most significant topic areas in GI endoscopy during the study year. Each Editorial Board member was directed to consider 3 criteria in generating candidate lists-significance, novelty, and global impact on clinical practice-and subject matter consensus was facilitated by the Chair through electronic voting. The 10 identified areas collectively represent advances in the following endoscopic spheres: artificial intelligence, endoscopic submucosal dissection, Barrett's esophagus, interventional EUS, endoscopic resection techniques, pancreaticobiliary endoscopy, management of acute pancreatitis, endoscopic environmental sustainability, the NordICC trial, and spiral enteroscopy. Each board member was assigned a consensus topic area around which to summarize relevant important articles, thereby generating this précis of the "top 10" endoscopic advances of 2022.

pT1 colorectal cancer: A treatment dilemma

The implementation of population screening programs for colorectal cancer (CRC) has led to a considerable increase in the prevalence pT1-CRC originating on polyps amenable by local treatments. However, a high proportion of patients are referred for unnecessary oncological surgeries without a clear benefit in terms of survival. Selecting the appropriate endoscopic resection technique in the moment of diagnosis becomes crucial to provide the best treatment alternative to each individual polyp and patient. For this, it is imperative to increase the optical diagnostic skill for differentiating pT1-CRCs and decide the appropriate initial therapy. En bloc resection is crucial to obtain an adequate histological specimen that might allow organ preserving therapeutic management. In this review, we address key challenges in T1 CRC management, explore the efficacy and safety of the available diagnostic and therapeutic approaches, and shed light on upcoming advances in the field.

Endoscopic Treatment of T1 Colorectal Cancer

Commonly accepted criteria for curative resection of T1 colorectal cancer include R0 resection with horizontal and vertical clear margins (R0), absence of lympho-vascular or vessel infiltration (L0, V0), a low to moderate histological grading (G1/2), low tumor cell budding, and limited (<1000 µm) infiltration into the submucosa. However, submucosal infiltration depth in the absence of other high-risk features has recently been questioned as a high-risk situation for lymph-node metastasis. Consequently, endoscopic resection techniques should focus on the acquisition of qualitatively and quantitively sufficient submucosal tissue. Here, we summarize the current literature on lymph-node metastasis risk after endoscopic resection of T1 colorectal cancer. Moreover, we discuss different endoscopic resection techniques with respect to the quality of the resected specimen.

Recent advances and current challenges in endoscopic resection with the full-thickness resection device

Endoscopic full-thickness resection (EFTR) has emerged as a viable technique in the management of mucosal and subepithelial lesions of the gastrointestinal tract (GIT) not amenable to conventional therapeutic approaches. While various devices and techniques have been described for EFTR, a single, combined full-thickness resection and closure device (full-thickness resection device, FTRD system, Ovesco Endoscopy AG, Tuebingen, Germany) has become commercially available in recent years. Initially, the FTRD system was limited to use in the colorectum only. Recently, a modified version of the FTRD has been released for EFTR in the upper GIT as well. This review provides a broad summary of the FTRD, highlighting recent advances and current challenges.

Dilemmas in the Clinical Management of pT1 Colorectal Cancer

Implementation of population-based colorectal cancer screening programs has led to increases in the incidence of pT1 colorectal cancer. These incipient invasive cancers have a very good prognosis and can be treated locally, but more than half of these cases are treated with surgery due to the presence of histological high-risk criteria. These high-risk criteria are suboptimal, with no consensus among clinical guidelines, heterogeneity in definitions and assessment, and poor concordance in evaluation, and recent evidence suggests that some of these criteria considered high risk might not necessarily affect individual prognosis. Current criteria classify most patients as high risk with an indication for additional surgery, but only 2-10.5% have lymph node metastasis, and the residual tumor is present in less than 20%, leading to overtreatment. Patients with pT1 colorectal cancer have excellent disease-free survival, and recent evidence indicates that the type of treatment, whether endoscopic or surgical, does not significantly impact prognosis. As a result, the protective role of surgery is questionable. Moreover, surgery is a more aggressive treatment option, with the potential for higher morbidity and mortality rates. This article presents a comprehensive review of recent evidence on the clinical management of pT1 colorectal cancer. The review analyzes the limitations of histological evaluation, the prognostic implications of histological risk status and the treatment performed, the adverse effects associated with both endoscopic and surgical treatments, and new advances in endoscopic treatment.

[Interventional endoscopy in gastroenterology]

Essential innovations in interventional endoscopy have significantly broadened the treatment armamentarium in gastroenterology. The treatment and complication management of intraepithelial neoplasms and early forms of cancer are increasingly being primarily addressed endoscopically. In cases of endoluminal lesions with no risk of lymph node or distant metastases, endoscopic mucosal resection and endoscopic submucosal dissection have become established as standards. For broad-based adenomas, coagulation of the resection margins should be performed in the case of a piecemeal resection. Submucosal lesions can be reached and resected by tunneling techniques. Peroral endoscopic myotomy in cases of achalasia is a new treatment option for hypertensive and hypercontractile motility disorders. In addition, endoscopic myotomy for gastroparesis has shown very promising results. In this article, new resection techniques and so-called third space endoscopy are presented and critically discussed.

Adverse events of endoscopic full-thickness resection: results from the German and Dutch nationwide colorectal FTRD registry

BACKGROUND AND AIMS

Endoscopic full-thickness resection (eFTR) is emerging as a minimally invasive alternative to surgery for complex colorectal lesions. Previous studies have demonstrated favorable safety results; however, large studies representing a generalizable estimation of adverse events (AEs) are lacking. Our aim was to provide further insight in AEs after eFTR.

METHODS

Data from all registered eFTR procedures in the German and Dutch colorectal full-thickness resection device registries between July 2015 and March 2021 were collected. Safety outcomes included immediate and late AEs.

RESULTS

Of 1892 procedures, the overall AE rate was 11.3% (213/1892). No AE-related mortality occurred. Perforations occurred in 2.5% (47/1892) of all AEs, 57.4% (27/47) of immediate AEs, and 42.6% (20/47) of delayed AEs. Successful endoscopic closure was achieved in 29.8% of cases (13 immediate and 1 delayed), and antibiotic treatment was sufficient in 4.3% (2 delayed). The appendicitis rate for appendiceal lesions was 9.9% (13/131), and 46.2% (6/13) could be treated conservatively. The severe AE rate requiring surgery was 2.2% (42/1892), including delayed perforations in .9% (17/1892) and immediate perforations in .7% (13/1892). Delayed perforations occurred between days 1 and 10 (median, 2) after eFTR, and 58.8% (10/17) were located on the left side. Other severe AEs were appendicitis (.4%, 7/1892), luminal stenosis (.1%, 2/1892), delayed bleeding (.1%, 1/1892), pain after eFTR close to the dentate line (.1%, 1/1892), and grasper entrapment in the clip (.1%, 1/1892).

CONCLUSIONS

Colorectal eFTR is a safe procedure with a low risk for severe AEs in everyday practice and without AE-related mortality. These results further support the position of eFTR as an established minimally invasive technique for complex colorectal lesions.

Current status of endoscopic full-thickness resection with the full-thickness resection device

Endoscopic full-thickness resection (EFTR) using the full-thickness resection device (FTRD) is an integral part of diagnostic and therapeutic endoscopy. Since its market launch in Europe in 2014, its safety and effectiveness have been proven in numerous studies. Adaptations in design as well as new techniques, such as hybrid EFTR, expand the spectrum of the FTRD system. The following review is intended to provide an overview of the clinical application and current evidence of EFTR with the FTRD system.

Long-term oncological outcomes of endoscopic full-thickness resection after previous incomplete resection of low-risk T1 CRC (LOCAL-study): study protocol of a national prospective cohort study

BACKGROUND

T1 colorectal cancer (CRC) without histological high-risk factors for lymph node metastasis (LNM) can potentially be cured by endoscopic resection, which is associated with significantly lower morbidity, mortality and costs compared to radical surgery. An important prerequisite for endoscopic resection as definite treatment is the histological confirmation of tumour-free resection margins. Incomplete resection with involved (R1) or indeterminate (Rx) margins is considered a strong risk factor for residual disease and local recurrence. Therefore, international guidelines recommend additional surgery in case of R1/Rx resection, even in absence of high-risk factors for LNM. Endoscopic full-thickness resection (eFTR) is a relatively new technique that allows transmural resection of colorectal lesions. Local scar excision after prior R1/Rx resection of low-risk T1 CRC could offer an attractive minimal invasive strategy to achieve confirmation about radicality of the previous resection or a second attempt for radical resection of residual luminal cancer. However, oncologic safety has not been established and long-term data are lacking. Besides, surveillance varies widely and requires standardization.

METHODS/DESIGN

In this nationwide, multicenter, prospective cohort study we aim to assess feasibility and oncological safety of completion eFTR following incomplete resection of low-risk T1 CRC. The primary endpoint is to assess the 2 and 5 year luminal local tumor recurrence rate. Secondary study endpoints are to assess feasibility, percentage of curative eFTR-resections, presence of scar tissue and/or complete scar excision at histopathology, safety of eFTR compared to surgery, 2 and 5 year nodal and/or distant tumor recurrence rate and 5-year disease-specific and overall-survival rate.

DISCUSSION

Since the implementation of CRC screening programs, the diagnostic rate of T1 CRC is steadily increasing. A significant proportion is not recognized as cancer before endoscopic resection and is therefore resected through conventional techniques primarily reserved for benign polyps. As such, precise histological assessment is often hampered due to cauterization and fragmentation and frequently leads to treatment dilemmas. This first prospective trial will potentially demonstrate the effectiveness and oncological safety of completion eFTR for patients who have undergone a previous incomplete T1 CRC resection. Hereby, substantial surgical overtreatment may be avoided, leading to treatment optimization and organ preservation. Trial registration Nederlands Trial Register, NL 7879, 16 July 2019 ( https://trialregister.nl/trial/7879 ).

Endoscopic Full Thickness Resection: A Systematic Review

Background Endoscopic full thickness resection (EFTR) is an emerging therapeutic option for resecting subepithelial lesions (SELs) and epithelial neoplasms. We aimed to systematically review the techniques, applications, outcomes, and complications of EFTR.

Methods A systematic literature search was performed using PubMed. All relevant original research articles involving EFTR were included for the review along with case report/series describing novel/rare techniques from 2001 to February 2022.

Results After screening 7,739 citations, finally 141 references were included. Non-exposed EFTR has lower probability of peritoneal contamination or tumor seeding compared with exposed EFTR. Among exposed EFTR, tunneled variety is associated with lower risk of peritoneal seeding or contamination compared with non-tunneled approach. Closure techniques involve though the scope (TTS) clips, loop and clips, over the scope clips (OTSC), full thickness resection device (FTRD), and endoscopic suturing/plicating/stapling devices. The indications of EFTR range from esophagus to rectum and include SELs arising from muscularis propria (MP), non-lifting adenoma, recurrent adenoma, and even early gastric cancer (EGC) or superficial colorectal carcinoma. Other indications include difficult locations (involving appendicular orifice or diverticulum) and full thickness biopsy for motility disorders. The main limitation of FTRD is feasibility in smaller lesions (<20–25 mm), which can be circumvented by hybrid EFTR techniques. Oncologic resection with lymphadencetomy for superficial GI malignancy can be accomplished by hybrid natural orifice transluminal endoscopic surgery (NOTES) combining EFTR and NOTES. Bleeding, perforation, appendicitis, enterocolonic fistula, FTRD malfunction, peritoneal tumor seeding, and contamination are among various adverse events. Post OTSC artifacts need to be differentiated from recurrent/residual lesions to avoid re-FTRD/surgery.

Conclusion EFTR is safe and effective therapeutic option for SELs, recurrent and non-lifting adenomas, tumors in difficult locations and selected cases of superficial GI carcinoma.

Deep Submucosal Invasion Is Not an Independent Risk Factor for Lymph Node Metastasis in T1 Colorectal Cancer: A Meta-Analysis

BACKGROUND & AIMS

Deep submucosal invasion (DSI) is considered a key risk factor for lymph node metastasis (LNM) and important criterion to recommend surgery in T1 colorectal cancer. However, metastatic risk for DSI is shown to be low in the absence of other histologic risk factors. This meta-analysis determines the independent risk of DSI for LNM.

METHODS

Suitable studies were included to establish LNM risk for DSI in univariable analysis. To assess DSI as independent risk factor, studies were eligible if risk factors (eg, DSI, poor differentiation, lymphovascular invasion, and high-grade tumor budding) were simultaneously included in multivariable analysis or LNM rate of DSI was described in absence of poor differentiation, lymphovascular invasion, and high-grade tumor budding. Odds ratios (OR) and 95% CIs were calculated.

RESULTS

Sixty-seven studies (21,238 patients) were included. Overall LNM rate was 11.2% and significantly higher for DSI-positive cancers (OR, 2.58; 95% CI, 2.10-3.18). Eight studies (3621 patients) were included in multivariable meta-analysis and did not weigh DSI as a significant predictor for LNM (OR, 1.73; 95% CI, 0.96-3.12). As opposed to a significant association between LNM and poor differentiation (OR, 2.14; 95% CI, 1.39-3.28), high-grade tumor budding (OR, 2.83; 95% CI, 2.06-3.88), and lymphovascular invasion (OR, 3.16; 95% CI, 1.88-5.33). Eight studies (1146 patients) analyzed DSI as solitary risk factor; absolute risk of LNM was 2.6% and pooled incidence rate was 2.83 (95% CI, 1.66-4.78).

CONCLUSIONS

DSI is not a strong independent predictor for LNM and should be reconsidered as a sole indicator for oncologic surgery. The expanding armamentarium for local excision as first-line treatment prompts serious consideration in amenable cases to tailor T1 colorectal cancer management.